While one preseason game is far from a tell-tale sign of an NFL team's impending season, Thursday night's 24-23 win over Pittsburgh shined a light on some of the strengths and weaknesses of the 2012 Eagles roster.

Let's take a look at some of the things we can take away from the preseason opener.

A Quality Backup QB Is Essential

Vick winces in pain after injuring his left thumb.

When Michael Vick injured his throwing hand early in the game, Philly fans froze with fear and awaited word on the severity. Before the diagnosis was released, the thought of entering the regular season without No. 7 behind center was a scary proposition for Eagles nation.

The Birds' backup quarterback options were suddenly cast into the spotlight, with Mike Kafka as the projected starter if Vick can't go.

Kafka, a fourth-round pick in last year's draft, has played in four games in his NFL career. He's thrown for a total of 107 yards with two interceptions and no touchdowns. Over his college career at Northwestern, Kafka threw for more interceptions (20) than touchdowns (19).

With Vick playing all 16 games only once in his nine years in the NFL, the likelihood of him missing at least a game or two is very high. Would you feel confident with Mike Kafka steering the ship in, say, Week 5 at Pittsburgh?

We got a glance at life with Kafka as QB on Thursday night. After Vick went down, Kafka was 5-of-9 for 31 yards and had one atrocious interception that was returned 54 yards to put the Steelers in scoring position. It was revealed that Kafka fractured his non-throwing hand and will be out at least three weeks.

This will make Nick Foles, the rookie who was a very bright spot in the Eagles' 24-23 victory in the preseason opener, the backup to Vick. Foles looked brilliant after a dreadful first half for the Eagles that left them trailing 10-0 at halftime. The rookie QB threw for 144 yards and two touchdowns in limited playing time.

Foles will now have a chance to build on his excellent debut and prove that he is the answer at backup QB.

The Defensive Line Is Exceptionally Deep and Talented

Philip Hunt and Brandon Graham both looked good vs. Pittsburgh

With starting defensive ends Trent Cole and Jason Babin both sidelined with injuries, the Eagles had an opportunity to showcase the depth of the D-Line. Phillip Hunt was one of the most impressive players in the game, recording two sacks and forcing a fumble while wreaking havoc on the Steelers' offensive line.

Rookie Vinny Curry, a second-round pick who was the Conference-USA Defensive Player of the Year as a senior, had an extraordinary Eagles debut. Curry was constantly getting pressure on the quarterback and led the team with five tackles.

Over the last two seasons of his college career at Marshall, Curry recorded a total of 23 sacks. He also had six forced fumbles as a senior, second most in college football. The Eagles may have found a steal here.

Brandon Graham, the player selected over Jason Pierre-Paul and Earl Thomas two years ago, may finally be poised to prove his worth. According to Dan Graziano of ESPN, Graham says that he is in the best shape of his life, and he's certainly tired of being labeled a bust.

He was solid on Thursday night, getting pressure on the QB and recording a sack. While the Eagles will always be lamented for selecting Graham over the two Pro Bowlers mentioned above, perhaps, he can develop into a good player in the Birds' rotation.

While the defensive ends look very strong, the depth at defensive tackle is also outstanding. With first-round pick Fletcher Cox, starter Cullen Jenkins, underrated Darryl Tapp and veteran starter Mike Patterson, who is recovering from offseason surgery, the Birds have one of the deepest, most talented defensive lines in the NFL.

With very serviceable players like Derek Landri and Antonio Dixon also in the fold, many teams will be lining up to see who the Eagles are forced to cut before the regular season kicks off.

Mychal Kendricks Will Improve the Linebacking Corps

Rookie LB Mychal Kendricks looked excellent in his Eagles debut.

Last season, the Eagles linebackers struggled mightily with the Wide-9 system implemented by Jim Washburn. The starters were exposed with regularity throughout the season, making the position an offseason priority.

Unlike years past, the Birds' front office actually addressed the glaring need. The team brought in former Pro Bowler DeMeco Ryans and drafted Mychal Kendricks from Cal in the second round.

While we didn't see much from Ryans in the preseason opener, Kendricks excelled in his Eagles debut. The 2011 Pac-12 Defensive Player of the Year looked fast and strong, tying the team high with five tackles, two of which were for a loss.

The Loss of Pro Bowl LT Jason Peters Could Be Crippling

LT Demetress Bell has already been demoted to second string.

The worst news of the offseason for Birds fans, by far, was the season-ending injury to Jason Peters. He was, perhaps, the best offensive lineman in all of football last season and played a large part in paving the way to a historic season for RB LeSean McCoy.

Keeping Vick healthy and creating running holes for LeSean McCoy are undoubtedly two of the biggest factors for the Eagles this season, and Peters was the best piece to ensure both.

When Peters went down with a torn Achilles, the Eagles quickly signed Demetress Bell, who took over for Peters in Buffalo after the Eagles lured him away. Bell only played six snaps on Thursday, but apparently, it was enough for Andy Reid and offensive-line guru Howard Mudd to demote him to second string.

King Dunlap, a seventh-round pick in 2008, now takes over as starter. Perhaps, the coaching staff is merely trying to motivate Bell to pick up his play with the demotion. Regardless, the downgrade from the dominant Peters could prove to be a crippling blow to the offensive line and production of the Eagles offense as a whole.